Creation of relatively wide drainage ditches in agricultural fields using commercially available earth working equipment can be time and fuel intensive. For example, commercially available rotary ditchers and V-plow ditchers have relatively narrow working widths and limited earth-moving capacity, thus requiring multiple passes across a field to make a larger ditch.
Examples of previous V-plow ditcher designs are disclosed in U.S. Pat. Nos. 2,136,911, 2,625,754, 2,668,376, 2,849,809, 2,911,735, 3,068,595, 3,206,879, 3,526,047, 3,711,970, 4,240,216, and 4,250,869, and include variable width designs where rear blades are movably mounted to adjust an angle at which the blades diverge.
U.S. Pat. No. 5,890,546 teaches an apparatus featuring a straight cross-wide blade with end-wing sections that pivot up and down between stowed and deployed positions to change the effective blade width, but the single straight blade intended for scraping, leveling or grading operations is not suitable for forming ditches.
U.S. Pat. No. 6,904,979 teaches an earth working apparatus with a V-shaped blade configuration at its front end and a straight cross-wide blade therebehind. The height of the rear blade and the angle of the front blade can be adjusted, allowing use of the apex of the front blade to dig a ditch with the front blade tilted down and the rear blade lifted entirely off the ground, but the narrow width of the front blade limits the achievable ditch width.
To address the need for more efficient production of large scale ditches, application has developed a unique large scale V-type ditcher capable of displacing greater volumes of soil per unit of towing distance to enable single-pass formation of ditches of greater depth and/or width, and in doing so has generated a number of unique configurations within the structure and layout of the machine.